He probably wants a buffer of calcium carbonate that will be in the rag board and could neutralize acids etc in the air. Good inkjet papers will have a buffer though. The rag board might also dampen differences in expansion of the aluminium and the print. Nothing has been tested of either combination. My gut feeling is that DiBond with a sealed surface is more inert than pure aluminium. In the sense that it will not oxidize like pure aluminium and weaken the adhesive bond with the paper in time. The polyethylene core is well protected to UV by the aluminium but on the edges, a milky white that will yellow in time but strength throughout is not affected. There will be some oxide formation on the 0.3 mm edges of the aluminium film but it will not spread. I had more prints mounted on aluminium as it could be cut accurately to the edge after mounting without deforming the edge. There has been a thread where users commented they could do the same with DiBond. I am not aware of any aluminium outgassing, it may act as a catalyzer like mentioned here but then the environmental conditions must be bad anyway.

Pure aluminium also has a sealed surface - an impervious oxide layer forms immediately on contact with air, dulling its appearance and preventing further corrosion. Anodised aluminium is even better protected.

Dibond is more rigid, but the polyethylene core will likely deteriorate before aluminium sheet will. It also carries a potential risk of delamination - we don't really know how long the bond will last.

Dibond is more rigid, but the polyethylene core will likely deteriorate before aluminium sheet will. It also carries a potential risk of delamination - we don't really know how long the bond will last.

From what I could see the thickest dibond that is commerically available is 5mm. I'm unsure of the flexiblity of that versus 5mm thick aluminum. You wouldn't have to worry about polyethylene deterioration as it is one of the most stable organic polymers. Delamination is said to be a minimal problem as there is very little thermal expansion and contraction of dibond.

I agree that dry mounting would be the way to go. Can one dry mount directly to aluminum or would you need to dry mount to rag board and then mount that to aluminum?

What I'm going to try with my own work this month in a 40x60 size is to dry mount the print to 4 ply rag board and then mount that to aluminum using the PVA book binders glue. That may be a mess to keep flat or it might not. I'll find out. That PVA is like concrete when dry and used by great museums to restore rare manuscripts and such.

Forget mounting with rice or wheat paste for something this big. I don't EVER want it coming up. The idea of removing a large print safely seems nearly impossible anyway, and who is going to be there in the future to do it. Humidity would play havoc with these kinds of adhesives.

I am wondering about one thing though. Would it be doable to paint the aluminum dibond with a titanium white acrylic to seal it completely and dry mount to that? I want to try that also. I know that dibond comes painted in black so I see no reason not to paint one white myself before dry mounting to it. (unless the dry mount press melted the acrylic paint in some way?/

I agree that dry mounting would be the way to go. Can one dry mount directly to aluminum or would you need to dry mount to rag board and then mount that to aluminum?

Forget mounting with rice or wheat paste for something this big. I don't EVER want it coming up. The idea of removing a large print safely seems nearly impossible anyway, and who is going to be there in the future to do it. Humidity would play havoc with these kinds of adhesives.

If you're going to dry-mount, you can mount directly on the aluminium - it's a more stable substrate than buffered mounting board.

Also, if you mount using heat-activated, non-acidic mounting tissue with a paper layer in between the two plastic layers, it should be easily removable just by applying heat. I personally wouldn't use the pressure-sensitive tissues, though, as the adhesives in these are non-removable and more susceptible to degradation.

Have you considered using hardened gelatin as a 'glue'? That stuff sticks pretty well to photos, and can be dissolved later on. (I'm not sure how inkjet prints would respond to a hot-water bath, though).

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What I'm going to try with my own work this month in a 40x60 size is to dry mount the print to 4 ply rag board and then mount that to aluminum using the PVA book binders glue. That may be a mess to keep flat or it might not. I'll find out. That PVA is like concrete when dry and used by great museums to restore rare manuscripts and such.

That's the problem - it sticks so hard that it's near-impossible to remove for future restoration! This is a problem they're now encountering with books bound using PVA.

Also, PVAs come in a variety of types - some are quite acidic, others are neutral to slightly alkaline. You don't want to use an acidic one...

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I am wondering about one thing though. Would it be doable to paint the aluminum dibond with a titanium white acrylic to seal it completely and dry mount to that? I want to try that also. I know that dibond comes painted in black so I see no reason not to paint one white myself before dry mounting to it. (unless the dry mount press melted the acrylic paint in some way?

Why would you do that? Paint peels. That's just another layer which can peel.

If you use anodised aluminium or anodised titanium, it's also sealed completely. Even straight aluminium panel is sealed completely by an oxide layer, although the oxide layer there is much thinner than that of anodised aluminium or titanium.

All this talk of black-and-white inkjet printing and silver print toning had me thinking - would it be possible or worthwhile to develop inksets based on the 'pigments' that give toned silver prints their colour? That is, using nanoparticle gold, silver selenide and silver sulfide, in addition to carbon, as 'pigments', in order to produce inkjet equivalents of toned silver prints, with even greater longevity. Naturally, you'd use a number of different particle sizes to simulate warm chloride/chlorobromide and cool bromide papers. Obviously this is out of the question for HP/Canon/Epson, and the inks would be expensive, but a high-end niche printer like Jon Cone might be able to make something of it. This might be a solution to pure carbon pigment only coming in one tone (I'm not sure if varying the size of the carbon nanoparticles would vary the colour tone of the pigment, but that could be another way of doing it).

By the way, have you seen or heard about the 'Extreme Printing' prints made by Cone Editions using triple-weight uncoated Japanese paper, a Roland printer with twelve custom inks and a heated ink/paper process? Any word on their longevity, particularly with the toned pigments? This could be another option for those very special jobs.

I don't think you will get the same result - chemicaly develop photography is completely different from inkjet. Particle are protected by gelatine, they are inside it, and they are mostly in form of filaments as they grow as a part of chemical development.

I am sure that new development in technology will give us some new exciting printing techinque, but going back is not the way. Everyone accepted digital photography - now it is time to accept printing as it is.

I don't think you will get the same result - chemicaly develop photography is completely different from inkjet. Particle are protected by gelatine, they are inside it, and they are mostly in form of filaments as they grow as a part of chemical development.

I am sure that new development in technology will give us some new exciting printing techinque, but going back is not the way. Everyone accepted digital photography - now it is time to accept printing as it is.

But, ultimately, the colour comes from the size and chemical composition of the particles (different-sized particles of the same compound will appear a different colour) while UV and chemical stability come from the chemical composition of the particles. It doesn't matter whether those particles are developed in a darkroom, precipitated out in a platinotype or squirted out of an inkjet printer.

I am wondering about one thing though. Would it be doable to paint the aluminum dibond with a titanium white acrylic to seal it completely and dry mount to that? I want to try that also. I know that dibond comes painted in black so I see no reason not to paint one white myself before dry mounting to it. (unless the dry mount press melted the acrylic paint in some way?/

john

John, DiBond and Alucobond come in a wide variety of surfaces, polyester coated, anodised, color anodised, etc etc. One DiBond quality has a surface to give a good bond to UV-curing inks like used in Durst inkjet printers etc. In my opinion that one will give an even better bond to adhesives than the DiBond surfaces already used for lamination of prints. I do not see DiBond as inferior to pure, anodised or etched aluminium (the last is made for glue constructions in coach building etc). The weak parts of any mounted print with said materials is in the print itself and the adhesives used. DiBond will not delaminate but on temperatures above 120 C. Ask Alcan that has acquired these composites with the purchase of Alcoa that did not invent DiBond or Alucobond either but merged with Alusuisse the original inventor of Alucobond etc. My brother used to work in that company for >30 years. Production still happens at the former Alusingen plant in Singen, Germany. The Alucobond comnposites were originally made for building cladding, truck panels, ship interiors. The range is widened with continuous inline production of full-aluminium honeycomb sandwich panels, good mounting product if the Alucobond sizes are too small for you. If I recall it correctly up to 15 meters length.